It was visible from St. Michael's Mount, from which news of it was carried via beacons.  Fear of "hellburners," which had wrought havoc during the Siege of Antwerp, caused confusion in this entity, and in a decisive battle much of its ammunition was not used due to [*] cramped spaces around cannons. After its defeat at Gravelines [gravel-EEN], unusually strong storms off the coast of Ireland caused it even more destruction. For 10 points, name this fleet defeated by Charles Howard and Sir Francis Drake, sent by King Phi
It was visible from St. Michael's Mount, from which news of it was carried via beacons.  Fear of "hellburners," which had wrought havoc during the Siege of Antwerp, caused confusion in this entity, and in a decisive battle much of its ammunition was not used due to [*] cramped spaces around cannons. After its defeat at Gravelines [gravel-EEN], unusually strong storms off the coast of Ireland caused it even more destruction. For 10 points, name this fleet defeated by Charles Howard and Sir Francis Drake, sent by King Philip II of a namesake Iberian nation to invade England.
It was visible from St. Michael's Mount, from which news of it was carried via beacons.  
Spanish {Armada} [or {Grande} y {Felicícima Armada}; accept {Great} and {Most Fortunate Navy}]